RESUMO
Background: Hypertension can be classified into different phenotypes based on systolic and diastolic blood pressure (BP) that carry a different prognosis and may therefore be differently associated with sympathetic activity. We assessed the association between cardiac autonomic function determined from continuous finger BP recordings and hypertensive phenotypes. Methods: We included 10,221 individuals aged between 18-70 years from the multi-ethnic HELIUS study. Finger BP was recorded continuously for 3-5 minutes from which cross-correlation baroreflex sensitivity (xBRS) and heart rate variability (HRV) were determined. Hypertension was classified into isolated systolic (ISH; ≥140/<90), diastolic (IDH; <140/≥90) and combined systolic and diastolic hypertension (SDH; ≥140/≥90). Differences were assessed after stratification by age (younger: ≤40, older: >40 years) and sex, using regression with correction for relevant covariates. For xBRS, values were log-transformed. Results: In younger adults with ISH, xBRS was comparable to normotensive individuals in men (ratio 0.92; 95%CI 0.84-1.01) and women (1.00; 95%CI 0.84-1.20), while xBRS was significantly lower in IDH and SDH (ratios between 0.67 and 0.80). In older adults, all hypertensive phenotypes had significantly lower xBRS compared to normotensives. We found a similar pattern for HRV in men, while in women HRV did not differ between phenotypes. Conclusions: In younger men and women ISH is not associated with a shift towards increased sympathetic control, while IDH and SDH in younger and all hypertensive phenotypes in older participants were associated with increased sympathetic control. This suggests that alterations in autonomic regulation could be a contributing factor to known prognostic disparities between hypertensive phenotypes.
Hypertension can be classified into different phenotypes based on systolic and diastolic blood pressure (BP) that carry a different prognosis. Impaired autonomic regulation is important in the pathogenesis of hypertension and independently associated with adverse cardiovascular outcomes.We analyzed 3-5 minutes continuous non-invasive finger blood pressure recordings performed in over 10.000 individuals participating in the HELIUS cohort study. From these measurements, short term heart rate variability (HRV) and cross correlation baroreflex sensitivity (xBRS) were determined using an automatic algorithm.In our analysis we observed pronounced differences in the relation between autonomic regulation and hypertensive phenotypes that depend on age and sex.Younger men and women (age 18-40 years) with isolated systolic hypertension had similar values for xBRS and HRV compared to normotensives, while isolated diastolic hypertension was associated with a shift towards increased sympathetic control. In contrast to our findings in younger individuals, all hypertensive phenotypes were associated with increased sympathetic control in older participants (age 40-70 years).This supports earlier studies showing prognostic differences and suggests that alterations in sympathovagal balance could be a contributing factor to the disparities between phenotypes.
